This is Amy Wagonar from the Historical Society of Michigan with a Michigan History Moment.

They stood as sentinels to keep watch over Michigan's forests.

Most are gone now, but in the early 20th century they stopped untold thousands of acres of Michigan forests from going up in smoke.

What were they?

Forest fire lookout towers.

During the 19th and early 20th centuries, loggers clear cut Michigan forests, leaving brush that often caught fire.

Forest fires killed hundreds of people and destroyed millions of acres of forests and clear cut land.

One early lesson learned was the critical importance of spotting small fires before they had time to grow.

Once a fire spread, it was impossible to extinguish with the primitive firefighting equipment of the time.

In 1910, Marcus Schaff, Michigan's first state forester, recommended that the state build a series of observation towers.

Men stationed in them could spot smoke and telephone the fire's location to firefighters before the blaze spread.

The Michigan Hardwoods Manufacturers association built the first fire tower, a wooden structure that stood 50ft high, near Lewiston in 1912.

In 1913, the state government's first fire tower went up in the new Higgins Lake State Forest.

Those early state towers were steel, 50 to 60ft high, and with a ladder that led to a small open platform at the top.

By 1926, at least 124 fire towers dotted the northern Michigan woods.

The second generation towers were more sophisticated.

They featured enclosed cabins atop steel towers that ranged from 100 to 150ft tall and had telephones and radios to communicate with headquarters.

The fire spotters were called towermen.

Requirements for the job included good eyesight, self reliance, knowledge of local geography, and proficiency in using maps and compasses to pinpoint a fire's location.

The fire towers proved their worth in 1911.

Before the fire towers were put up, fires burned more than 152,000 acres of forests.

In 1922, fire towers reduced the loss to 36,000 acres.

Fire tower usage peaked in the 1940s.

After World War II, the Department of Conservation began using airplanes to spot forest forest fires.

The state discontinued their use in the 1960s and sold most of them for scrap metal.

A few remain in Michigan, and the Udell Lookout Tower in Manistee county is listed on the National Register of Historic Places.

This Michigan history moment was brought to you by michiganhistorymagazine.org.